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Dear GlusterFS users,<br>
<br>
We are trying to use some C programs that rely on direct I/O operations on files residing on a GlusterFS volume composed of ext4 bricks.<br>
<br>
It is our understanding that this should be possible if we specify the <span style="font-family: Courier New;">
</span><i style="font-family: Courier New;">direct-io-mode=enable</i> option when mounting the volume, but for some reason we get the following error message when calling the
<i style="font-family: Courier New;">open()</i> system call with the <i style="font-family: Courier New;">
O_DIRECT</i> flag:<i> "Invalid arguments"</i>.<br>
<br>
The same system call succeeds on the local file system.<br>
<br>
<br>
System info:<br>
<div style="margin-left: 40px;">CentOS 6.2<br>
GlusterFS 3.2.5<br>
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<br>
gluster volume info:<br>
<blockquote><font size="2"><span style="font-family: Courier New;">Volume Name: rdmaVol</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Type: Distribute</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Status: Started</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Number of Bricks: 2</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Transport-type: rdma</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Bricks:</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Brick1: node01:/home/gfs</span><br style="font-family: Courier New;">
<span style="font-family: Courier New;">Brick2: node02:/home/gfs</span></font><br>
<br>
</blockquote>
mount command:<br>
<blockquote><font style="font-style: italic;" size="2"><span style="font-family: Courier New;">$ mount -t glusterfs -o direct-io-mode=enable node01:/rdmaVol /mnt/gfs</span></font><br>
<br>
</blockquote>
We would really appreciate your help and suggestions! Please let us know if you need any additional information.
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